Prior art disc recorders have been able to increase track density by using a special buried servo track which enables detection of track eccentricity and subsequent servoing of the head carriage mechansim. Another form of this same technique uses a reference track about the circumference of the disc or simply adds a servo disc. Either method requires the recording and reproduction of a special signal for this purpose only. Thus, such systems are not capable of using magnetic discs which lack this reference or servo track. Increasing track density by using a fixed, non-removable hard disc can be accomplished simply by greater precision in manufacturing the discs and the servo system. Because of the inherent mechanical sloppiness of a flexible disc (known in the trade as a "floppy" disc), however, increased track density is harder to achieve in these devices.
What is needed is a floppy disc whose information storage ability will render it competitive with the capabilities of the standard hard discs. Such discs would not only be useful for standard software applications, but could be used for storing up to fifty digital video slides on one three and a half inch disc or for storing up to twenty x-ray images in digital form.